Jim: You may not have seen the 2 references below. They list:
Remove back plate attaching bolts and washers, and remove back plates,
shims, and insulators (if applicable).Install insulator shims (typically used with metallic lining) and spacers as applicable.http://www.cessnat50.org/media/manuals_ ... veland.pdfhttp://www.myrv10.com/tips/maintenance/ ... e_2009.pdfIn the 2 references they provide break in procedures. Note the tail dragger caution.
They discuss to ensure the cylinder must be able to move in the torque plate freely.
The 1st reference list a minimum stack up
If linings are still usable or are replaced, measure the cumulative thickness of two linings, disc, and pressure plate as shown in Figure A1-1. If the stack measures less than 1.00 (1-inch) with good linings (linings above .100 inch), the brake disc is considered below minimum wear thickness and should be replaced. My only observation: With less shim, the brakes will most likely come on sooner and possible have brake drag (lining staying in contact if not enough clearance) upon release.
With new linings and a serviceable disc and free moving cylinder you should be okay.